What is the treatment for pustular lesions in children?

Treatment of Pustular Lesions in Children

Immediate Diagnostic Approach

The first priority is to distinguish infectious from non-infectious pustular eruptions, as infectious causes require immediate antimicrobial therapy while non-infectious causes may worsen with inappropriate treatment. 1

Essential Rapid Diagnostic Tests

• Perform a Tzanck smear first - this is the single most important rapid diagnostic test that detects herpetic infections (multinucleated giant cells) and differentiates infectious from non-infectious pustular eruptions (eosinophils vs neutrophils). 1
• Gram stain should be performed immediately to detect bacterial infections, particularly Staphylococcus aureus and Listeria monocytogenes in neonates. 1
• Potassium hydroxide (KOH) preparation is essential to identify fungal infections, particularly candidiasis. 1
• Bacterial, viral, and fungal cultures should be obtained before initiating therapy. 1

Treatment Algorithm by Etiology

Infectious Pustular Lesions

For bacterial impetigo or localized staphylococcal infections, apply mupirocin ointment 2% three times daily to affected areas. 2

• The treated area may be covered with gauze dressing if desired. 2
• Re-evaluate patients who do not show clinical response within 3-5 days. 2
• Avoid use on mucosal surfaces and discontinue if sensitivity or chemical irritation occurs. 2
• For systemic bacterial infections or sepsis, initiate appropriate intravenous antibiotics immediately based on culture results. 1

Non-Infectious Pustular Psoriasis

Mild to Moderate Pustular Psoriasis

Begin with topical calcineurin inhibitors (tacrolimus 0.1%) for facial and genital involvement, as these show excellent improvement within 30 days without the risk of skin atrophy. 3

• Combination therapy with topical vitamin D analogs and topical corticosteroids is effective for plaque-type pustular psoriasis. 3
• Use moderately potent (class III) topical corticosteroids for body lesions to balance efficacy with safety. 4
• Avoid high-potency or ultra-high-potency corticosteroids in children 0-6 years due to high risk of HPA axis suppression from their elevated body surface area-to-volume ratio. 3

Severe, Unstable, or Generalized Pustular Psoriasis

Acitretin is recommended as the first-line systemic therapy for pustular psoriasis in children at 0.1-1 mg/kg/day, with response typically seen within 3 weeks. 5

• Acitretin is particularly effective for pustular variants and is non-immunosuppressive. 5
• Acitretin combined with narrowband UVB phototherapy is synergistic and allows dose reduction of both agents. 5
• Monitor for mucocutaneous dryness (most common side effect) and hyperlipidemia (transient and dose-dependent). 5
• Absolutely avoid acitretin in female adolescents approaching childbearing potential, as it remains stored in the body for up to 3 years when reverse-esterified to etretinate in the presence of alcohol. 5, 4

For rapid control of severe, unstable pustular psoriasis, cyclosporine 2-5 mg/kg/day achieves skin clearance in approximately 4 weeks. 5

• Cyclosporine is excellent for crisis management and rapidly progressive disease. 5
• Initiate at the higher end of the dosing range and reduce to the lowest effective maintenance dose. 5
• Use as short-term intermittent therapy rather than long-term maintenance. 6

Refractory Pustular Psoriasis

Infliximab 5 mg/kg IV at weeks 0,2, and 6, then every 8 weeks is recommended for severe pustular psoriasis unresponsive to other systemic medications, rapidly progressive, unstable, or life-threatening disease. 5

• Infliximab can be used as monotherapy or combined with methotrexate. 5
• This is particularly effective for pustular variants that have failed conventional systemic therapy. 5

Benign Transient Neonatal Pustulosis

For erythema toxicum neonatorum, transient neonatal pustular melanosis, and infantile acropustulosis, no treatment is required as these are self-limited conditions. 1, 7

• These diagnoses spare the neonate from invasive sepsis evaluation, harmful antibiotic therapy, and prolonged hospitalization. 1
• Reassurance and observation are appropriate once infectious causes are excluded. 1

Critical Safety Considerations

Monitoring Requirements

• Routine clinical and laboratory monitoring is mandatory during systemic therapy with acitretin, cyclosporine, or biologics. 5
• For biologics, monitor for injection site reactions and increased infection risk. 5
• Screen for latent tuberculosis before initiating biologic therapy, particularly TNF-α inhibitors. 5

Common Pitfalls to Avoid

• Never abruptly discontinue high-potency corticosteroids, as this causes significant rebound flares. 3
• Do not use mupirocin on mucosal surfaces or in patients with moderate-to-severe renal impairment due to polyethylene glycol absorption. 2
• Do not delay infectious disease workup in any neonate with pustules - sepsis must be ruled out first. 1
• Avoid methotrexate in female adolescents without reliable contraception due to teratogenicity (pregnancy category X). 5

Age-Specific Precautions

• Infants and children 0-6 years require extreme caution with topical corticosteroids and limited quantities with clear application instructions. 3
• Adolescents approaching childbearing potential should avoid acitretin and use methotrexate only with reliable contraception. 5, 4
• Phototherapy requires patient cooperation and is generally reserved for children old enough to tolerate 2-3 weekly sessions. 4